How does Jiangsu Foundry do a good job in surface polishing treatment of cast iron castings?
Mechanical polishing of cast iron parts: Mechanical polishing is divided into coarse polishing and fine polishing. Coarse polishing is performed on electric polishing discs with a speed of 200-300 rpm using coarse woolen fabric. During the rough polishing process, it is necessary to sprinkle coarser chromium oxide, aluminum oxide, or magnesium oxide polishing solution appropriately, and keep the fabric on the polishing disc moist. During the rough polishing process, it is necessary to hold the sample tightly and move it back and forth along the radial direction of the polishing disc. The applied pressure should be evenly adjusted, and the pressure should not be too high. At the beginning of polishing, it is necessary to sprinkle some polishing liquid occasionally. In the future, gradually reduce the pressure and reduce the concentration of the polishing solution until the fine grinding marks disappear, flat and bright, and there are no black spots. The rough polished sample is washed with water and then subjected to fine polishing to remove the grinding marks left by the rough polishing and make the grinding surface bright and flat. The polishing machine used for fine polishing is basically the same as the equipment used for coarse polishing, with a speed of 150-200 rpm.
Cast iron spot polishing: The metal ions separated from the workpiece and the phosphoric acid in the polishing solution form a phosphate film that adsorbs on the surface of the workpiece. This type of mucosa is thinner at the convex part and thicker at the concave part. Due to the high current density at the convex part, it dissolves quickly. As the mucosa flows, the concavity and convexity change continuously, and the rough surface is gradually flattened.
The above is an introduction to how to do a good job in polishing cast iron parts. If you still don't understand anything, you can directly communicate with our customer service. We are dedicated to serving you. Thank you for watching.